gpsbabel_format_option is any option handled by the specified GPSBabel format (refer to the documentation of each GPSBabel format)

features= can be used to modify the type of features that GPSBabel will import. waypoints matches the -w option of gpsbabel commmandline, tracks matches -t and routes matches -r. This option can be used to require full data import from GPS receivers that are slow and for which GPSBabel would only fetch waypoints by default. See the documentation on Route and Track modes for more details.

filename can be an actual on-disk file, a file handled through the GDAL virtual file API, or a special device handled by GPSBabel such as "usb:", "/dev/ttyS0", "COM1:", etc.. What is actually supported depends on the used GPSBabel format.

Alternatively, for a few selected GPSBabel formats, just specifying the filename might be sufficient. The list
includes for now :

garmin_txt

gdb

magellan

mapsend

mapsource

nmea

osm

ozi

igc

The USE_TEMPFILE=YES configuration option can be used to create an on-disk temporary GPX file instead of a in-memory one,
when reading big amount of data.

Write support

The driver relies on the GPX driver to create an intermediate file that will be finally translated by GPSBabel to
the desired GPSBabel format. (The GPX driver does not need to be configured for read support for GPSBabel write support.).

The support geometries, options and other creation issues are the ones of the GPX driver. Please refer to its documentation for more details.

The syntax to specify an output datasource is : GPSBabel:gpsbabel_file_format[,gpsbabel_format_option]*:filename
where :